ANT 101 Final
Geographic distribution of H erectus
Homo erectus left Africa ~1.8 mya • Dispersed to Asia and Eurasia (Central and Western) • Global climate and habitat changes caused widespread movement • Oldest fossils found in Dmanisi, Georgia
Post-Orbital Constriction
Narrowing behind the orbits
Francis Galton
The philosophy of "race improvement"; idea that controlled selective breeding can improve the human species ▪ Eugenics movement in the Europe and the US ▪ Sterilization and anti-immigrant movement ▪ Nazi pseudoscience and idea of racial purity
Earliest Human Fossil Sites
Earliest fossils in Africa & Middle East (80,000- 190,000 ya), followed by Eurasia, Australia, and finally the Americas
(Cranial)Sagittal crest
Elevated bone along the midline of the cranium - Attachment site for muscles a bony ridge on the top of the skull to which the jaw muscles are attached.
Orthognathic
Flat face Having a non-projecting lower facial skeleton
Evidence for Ritual
Evidence for intentional and ceremonial burial ▪ Grave goods ▪ Forms of postmortem modification (e.g., dismemberment, defleshing)
Describing Human Variation
Historically, the dominant paradigm has been race and racial classification ▪ Used in many different ways: ▪ Continental ancestry ▪ Nationality ▪ Religious identity ▪ Ethnic or cultural group ▪ Race is often used in a social sense and can have biological consequences
Gracile
Slender bodied (versus robust)
Johann Blumenbach (1752-1840)
the socalled "father of physical anthropology" ▪ Defined the "classic" races in 1795 ▪ Caucasian ▪ Mongolian ▪ Ethiopian ▪ American ▪ Malay ▪ Field moves towards focus on the skull, era of measurement, and explicit hierarchy/ranking
Multiple Dispersals and Assimilation
Most supported and accepted view now - Multiple dispersals of genus Homo out of Africa • "Out of Africa,Again and Again" - Modern humans originated in Africa, ventured out, and interbred with populations of archaic Homo sapiens • Evidence: - Recent fossil and DNA evidence support this view
Neandertal key sites
NeanderValley (Germany) -La Chapelle (France) -Shanidar (Iraq) -Mt. Carmel sites (Israel)
Australopithecus
Thrived in Africa for over 2 million years ▪ Habitual bipeds ▪ Small-bodied (3.5 - 5 feet tall) ▪ Slightly larger brains (yet still small) ▪ Large molars with thick enamel (fibrous diet) ▪ Small canines and reduced honing complex ▪ Limited tools and culture ▪ Lived in various habitats in east, central and south Africa (e.g., open woodlands, grasslands)
Foramen magnum
Big hole"; located on the inferior region of the skull A large opening at the base of the skull through which the brain connects to the spinal cord.
Zygomatic arch
Cheek bone
H heidelbergensis Cranial Features
Compared to H. erectus • Supraorbital tori: Less prominent and separated (arching), yet still large • Sagittal keel and occipital torus: Less pronounced • Robusticity: Decreased, yet some thickness of cranial bones • Brain size: Larger and vertical sides • Some within modern human ranges
Argument
Early Homo fossils typically classified into two species (although debated) • Homo habilis • Homo rudolfensis
Nuchal
Posterior side of the neck Back of neck
Australopithecus anamensis
First Australopithecine ▪ Location: Northern Kenya ▪ Age: ~4.5 - 3.9 mya ▪ Ape-like features ▪ Slight canine/premolar honing complex ▪ Hominin-like features ▪ Bipedal modifications in lower limbs ▪ Molars with thick enamel ▪ Potential ancestors for later Australopithecines (e.g., A. afarensis)
Neandertal Culture
Hunters • Able to hunt large game (e.g., bison, deer) in coordinated groups using long spears • Evidence of healed injuries similar to rodeo athletes • Tooth wear from processing hides • Provided assistance to injured individuals? • Buried Dead • Deliberately positioned in graves • Some evidence of "grave goods" • Symbols and Ornaments • Necklaces (e.g., shells) • Body pigments
determinant of genus Homo
Large brain relative to body size - 40% increase in brain size among early Homo compared to Australopithecines - Also, smaller teeth and larger body size
Neandertal Cranial Features
Large brain size (mean: ~1520 cc) ▪ Long skull ("football" shaped) ▪ Prominent, arching brow ridges ▪ Mid-facial prognathism ▪ Wide nasal aperture ▪ Retromolar gap: Behind 3rd molar ▪ Occipital bun ▪ No chin
Dental Arcade
Shape made by the rows of teeth in the upper jaw
Archaic vs Anatomically Modern Humans
Specific changes in the cranium distinguish "archaic" and "modern" humans Modern: • Small brow ridge • Flat face • Flat, small cheekbones • Small teeth Archaic: • Large brow ridge • Projecting face • Large, wide cheekbones • Larger teeth
Homo ergaster
African • ~1.8 mya - 800 kya • East & South Africa • Separate species: Homo ergaster? • Large brain (~750-900 cc) • Lack of sagittal keel • Less robust supraorbital torus • Thinner cranial bones
Australopithecus bahrelghazali
Age: ~3.3 mya • Location: N. central Africa in Chad - Evidence for broader distribution of Australopithecines • Mandible fragment only • Highly debated hominin fossil - Some experts suggest that the mandible belongs to A. afarensis - Others suggest that it represents a separate species - "Lumpers" vs. "Splitters"
Recent African Origin ("Out of Africa")
Anatomically modern humans evolved in Africa (~150 - 200,000 years ago) and then ventured out of Africa and globally dispersed • RAO-Replace: Modern humans replaced archaic humans with minimal interbreeding • RAO-Hybrid: Modern and archaic humans engaged in interbreeding
Art
Elaborate cave paintings (by ~40,000 years ago) ▪ Example: Lascaux Caves in France (date to ~17,000 years ago) ▪ Painted onto the walls using mineral pigments Venus and Caves of Lascaux showing game
Carolus Linnaeus (1758)
First systematic attempt at human classification ▪ Assigned varieties or "races" ▪ Homo sapiens afer (Africans) ▪ H.s. americanus (American Indians) ▪ H.s. asiaticus (Asians) ▪ H.s. europaeus (Europeans) ▪ H.s. ferus ("wild men") & H.s. montrous ▪ Most early (18th & 19th century) classifications used some type of ranking system ▪ "Great Chain of Being": A universal hierarchical ladder ▪ Implied or explicit rank order of superiority from European to Asian to American to African ▪ Reflected worldview of Europeans at the time
Early Hominin Evolution
From late Miocene to early Pliocene
Laetoli (Tanzania) Footprints
-3.7-3.5 mya -preserved through volcanic ash footprints of two bipedal hominids preserved after a volcanic eruption and rainfall; 3.6mya
Prognathism
Anterior projection of the midface Projection of the jaw(s) beyond the projection of the forehead.
Asian H Erectus
Asian • ~1.8 mya - 143 kya • West, East & SE Asia (Java, China) • "Classic" H. erectus traits • Large brain (~750-1250 cc) • Strong sagittal keel • Strong supraorbital torus • Thick cranial bones
Modern Human Anatomical Features
Average cranial capacity: ~1350 cc • Small teeth • Small face • Canine fossa: Depression on the surface of maxillary bone caused by the socket of the canine tooth • Well-defined chin • Rounded skull with vertical forehead • Reduced supraorbital torus
Neandertal Fate
Between 30 - 40,000 years ago, Neandertals were joined in Europe by anatomically modern Homo sapiens • Genetic evidence indicates occasional interbreeding • Various hypotheses regarding the fate of Neandertals • Examples: Parasites and pathogens, competitive replacement, failure or inability to adapt to climate change
Tools
Blade industry ▪ Made from stone flakes ▪ Flakes are twice as long as they are wide ▪ Wood, ivory, and bone carved to produce small tools (e.g., fishhooks, needles) ▪ Atlatl (i.e., spear-thrower) ▪ Able to better exploit surrounding environment (e.g., collect fish, increased food processing) ▪ Regional variation and "style"
Oldowan Tools
Commonly regarded as first stone tools in the archaeological record • ~2.5 mya • Involve simple modifications • Potentially associated with increased meat eating • Core: Possibly used for heavy-duty chopping, butchering, and fracturing (e.g., bones) • However, some suggest that the core was not the main tool • Flake: Likely used for cutting, slicing, and sawing (e.g., wood, meat, grass) • Associated with earlier hominin species?
Modern Human PostCranial Features
Compared to Neandertals ▪ Taller with a more slender body ▪ Thinner, less robust bones ▪ Longer limbs ▪ Longer trunk ▪ Cylindrical-shaped rib cage
Homo floresiensis
Discovered in 2004 • Age: ~100 - 12 kya • Location: Flores, Indonesia • Traits: • Tiny body (~3 ft.) and brain (~400 cc) • Skeletal similarities link H. floresiensis to H. erectus • Large supraorbital torus and thick cranial bones • Homo dentition • Human-like bipedal adaptations and modern proportions • Result of isolated dwarfism?
Australopithecus Diversification and Dispersal
Dispersal into South Africa ~3 mya • Diversification into gracile and robust forms • Gracile (South Africa only) -Australopithecus africanus • Robust (South Africa and East Africa) -Paranthropus robustus, boisei, aethiopicus
Acheulean Tool Industry
First appear in Africa ~1.6 - 1.4 mya • Found mostly in Africa and western and central Eurasia; few locations in east Asia • Bifacial Flaking: Flaked on both sides • Strong and sharp hand axes • Preconceived shape; required a "mental template" • Carried from place to place • Used to process meat; also, possibly wood and bones
Multiregional Evolution/Continuity
Homo erectus left Africa and then evolved into modern humans in several different locations throughout the world • All populations experienced similar patterns of change (i.e., continuity) due to gene flow and common modes of adaptation • Differences in genes and morphology due to adaptations to local environments • Modern humans are the most recent morphological form of Homo sapiens, which have been around for ~2 million years
Honing/Shearing Complex
Lower first premolar is sharpened from rubbing against the upper canine - Leads to honing of surfaces on both teeth Sectorial premolar: First lower premolar that exhibits compression due its role as a shearing surface - Diastema: Space separating teeth of different functions - Reduced among early hominin groups
Upper Paleolithic Cultural Period
Material Culture among Modern Humans ▪ Started ~40 kya ▪ Advent of modern humanity ▪ New complexity in tools, hunting and foraging behavior, and symbolic expression 12,000 year old bone needle
Hominin
Member of the subfamily Homininae ▪ Includes humans and ancestors in our lineage since LCA with apes ▪ Has replaced the term "Hominid" Defined by habitual bipedal adaptation Earliest Hominins ▪ ~5-7 million years ago (End of Miocene) ▪ Evolved in Africa and were there exclusively until ~2 mya Hominin evolution extremely complicated and species-rich • Often, multiple species alive at one time • Multiple hominin adaptive radiations • Not one linear progression from simple to complex
Turkana Boy
Most complete H. erectus skeleton ▪ Skull, pelvis, limb bones, ribs, and vertebrae ▪ Age: ~1.65 mya ▪ Location: W. Turkana, Kenya, E. Africa ▪ Brain size: ~900 cc ▪ ~8 years old, ~5'3" tall, and ~100 lbs. ▪ Similar stature to modern humans in equatorial Africa ▪ Long legs
Pleistocene
Rapid climatic fluctuations occurred during the Middle Pleistocene (900 -130 kya) and Late Pleistocene (130 - 10 kya) • Glaciations: Associated with colder temperatures and continental ice sheets covering northern continents • Interglacials: Associated with warmer temperatures and reduction in continental ice sheets • Major effects in Europe and northern Asia; influenced gene flow and drift
Understanding Human Variation
Recent origin (within last 200,000 years) ▪ Widespread geographic distribution ▪ Patterns of gene flow and isolation ▪ Exposure to diverse environmental factors Humans are very similar in genotype - Genetic make-up of an organism • However, humans are significantly different in phenotype - Physical manifestation of the genotype (i.e., observable characteristics) • Difference between describing and understanding human variation
Supraorbital torus
Robust piece of bone above orbits - Variability in prominence of brow ridge
Homo heidelbergensis
Transitional species between H. erectus and later hominins (e.g., modern humans and Neandertals) - Pronounced supraorbital torus, thick cranial bones, and no chin, yet larger brains and reduced dentition ~600,000 - 200,000 years ago Africa, Europe, and Asia (China) Cranial Capacity:~1100 - 1450 cc Cranial and Dental:Less prominent and separated supraorbital tori; less pronounced sagittal keel; flatter face; decreased robusticity of cranial bones; larger brain size Postcranial: Tall (i.e., lower legs were relatively long); robust postcranial traits (e.g., leg bones were thick and strongly built) -Likely ancestor to bother Neandertals and anatomically modern humans; transitional species between Homo erectus and later hominins (e.g., modern humans and Neandertals)
Middle Pleistocene Hominins
Widely distributed: Africa,Asia, and Europe • For the first time, Europe becomes more densely occupied (e.g., France, Spain, Germany, Hungary, Italy) • Replacing, or coexisting, with earlier hominins (e.g., Homo erectus) in previously exploited habitats; range was not vastly extended Homo heidelbergensis
Homo erectus
~ 1.8 million years ago - 143,000 years ago Africa, Asia, and Central/Western Eurasia ~727 - 1251 cc Cranial and Dental: Larger brain size; facial and dental reduction; low forehead; long and low braincase; pronounced supraorbital torus; pronounced occipital/nuchal torus; sagittal keel/ridge; thick cranial bones; cranium broadest at base; shovel-shaped incisors Postcranial: Larger body size (5.3 - 5.9 ft.); change in proportions (longer legs, shorter arms); similar stature to modern humans in equatorial Africa - First hominin to disperse from Africa; associated with Acheulean tool industry; first definitive evidence of controlled fire; the fossil "Turkana Boy" is the most complete Homo erectus skeleton
Homo neandertalensis
~130,000 - 30,000 years ago Europe and Western Asia ~1200 - 1740 cc Cranial and Dental: Large brain size; long skull ("football" shaped); prominent, arching brow ridges; midfacial prognathism; wide nasal aperture; retromolar gap; occipital bun; no chin Postcranial Large, robust, and muscular bodies; short limbs; barrel-shaped rib cage - Associated with Mousterian tool industry; buried dead; skilled large game hunters; evidence of using symbols and ornaments
Paranthropus robustus
~2.0 - 1.5 million years ago South Africa ~530 cc Cranial and Dental: Small brain size; pronounced sagittal crest; flared zygomatic arches; flat face; small incisors and canines Postcranial: Long arms but bipedal feet; similar hands to later hominins -Adaptations associated with a robust diet (i.e., low quality, hard-toprocess, fibrous foods); lived in mixed-sex groups of multiple adults and offspring
Homo habilis
~2.0 - 1.6 million years ago East and South Africa ~503 - 661 cc Cranial and Dental: Encephalization (i.e., expanded brain size relative to body size); large incisors, smaller molars; precision grip (i.e., able to grip objects forcefully with hands); relatively prognathic face; no sagittal crest Postcranial: Pelvic and lower limb morphology display bipedal adaptations -Associated with Oldowan tool industry (commonly regarded as first stone tools in the archaeological record); name means "handy man"
Paranthropus boisei
~2.3 - 1.3 million years ago East Africa (Ethiopia, Tanzania, and Kenya) ~410 - 530 cc Cranial and Dental: Small brain size; pronounced sagittal crest; flared zygomatic arches; broad, dish-shaped face; very large molar teeth; parabolic dental arcade Postcranial: Few postcranial bones associated with this species -Adaptations associated with a robust diet (i.e., low quality, hard-toprocess, fibrous foods); lived in mixed-sex groups of multiple adults and offspring
Paranthropus aethiopicus
~2.5 - 2.3 million years ago East Africa (Ethiopia and Kenya) ~410 cc Cranial and Dental: Small brain size; dish-shaped face; pronounced sagittal crest; flared zygomatic arches; extreme facial prognathism; very large molar teeth Postcranial: Limited postcranial evidence of this species -Adaptations associated with a robust diet (i.e., low quality, hard-toprocess, fibrous foods); lived in mixed-sex groups of multiple adults and offspring
(Anatomically modern) Homo sapiens
~200,000 years ago - Present Geographical Location Throughout the world Cranial Capacity (if available) ~1000 - 2000 cc Cranial and Dental: Rounded skull with widest point toward top (on sides of parietals); canine fossa; tall, vertical forehead; small teeth; small face; well-defined chin; reduced supraorbital torus Postcranial: Tall with a slender body; thin, less robust bones; long limbs; long trunk; cylindrical shaped rib cage -Associated with Upper Paleolithic tool industry; evidence of cave art, symbolism, portable art, personal ornamentation, and ritual
Australopithecus africanus
~3.0 - 2.4 million years ago South Africa (e.g., Sterkfontein and Taung sites) ~450 - 500 cc Cranial and Dental: Small brain size; small canines and incisors; less prognathic face Postcranial Characteristics: Bipedal adaptations (e.g., curved lumbar region of vertebrae); arboreal adaptations (e.g., long arms, slightly divergent big toe) -Lived in woodland environment; Famous "Taung child" fossil discovered by Raymond Dart in 1924
Australopithecus afarensis
~3.9 - 3.0 mya Eastern Africa (e.g., Hadar and Laetoli sites) ~350 - 500 cc Cranial and Dental: Small brain size; prognathic face; anteriorly placed foramen magnum; reduced canine size yet still large; large molars with thick enamel; parallel-shaped dental arcade Postcranial:Lower limb proportions intermediate between ape and human (e.g., long arms); curved, long phalanges; pelvic and lower limb (e.g., femur, feet) morphology indicate of habitual bipedalism -Best-known early hominin; fossils from over 70 individuals have been discovered in east Africa; the fossil "Lucy" represents nearly 40% of a complete Australopithecus afarensis skeleton; Laetoli footprints found in association with Australopithecus afarensis fossils
Ardipithecus ramidus
~4.4 million years ago Middle Awash region of eastern Africa (Northern Ethiopia) ~300 - 350 cc Cranial and Dental: Non-honing canine; reduced prognathism; forward (anterior) foramen magnum Postcranial: Arboreal hands and feet (e.g., grasping big toe); mosaic foot (i.e., includes both arboreal and terrestrial features); long arms; bipedal pelvis and femur -Lived in a woodland environment; morphological characteristics suggest moved bipedally on the ground but was also adept at moving in the trees
Sahelanthropos tchadensis
~6 - 7 million years ago Central Africa (Northern Chad) Cranial capacity: < 400 cc Cranial and Dental Characteristics: Intermediate foramen magnum; small brain size; large brow ridges and cranial crests; small face No postcranial fossils have been found -Odd mixture of ape- and hominin-like features; expands the range of early hominins outside of eastern Africa
Orrorin tugenensis
~6 million years ago Eastern Africa (Central Kenya) Cranial capacity is unknown since no fossil material from the skull has been recovered Cranial and Dental:Thick molar enamel; partial honing canine Postcranial: Curved hand bones; long femoral neck and femur angled medially (valgus angle) -Postcranial material indicate bipedal locomotion; fossil name means "original man"
Australopithecus afarensis
• Best-known early hominin - Fossils of over 70 individuals from 6 different sites in E. Africa - "Lucy": Represents nearly 40% of a complete skeleton; ~3.2 mya • Age: ~3.9 - 3.0 mya Cranial features: 350 - 500 cm3, Prognathic face, Anteriorly placed foramen magnum Dental features: Canines reduced but still large, Large molars with thick enamel, "U-shaped"/parallel dental arcade Postcranial: Habitual Bipedalism - Pelvic morphology - Lower limb proportions intermediate between ape and human • Arboreal Adaptations: Curved, long phalanges, Long arms • Pronounced Sexual Dimorphism: Debated among paleoanthropologists • Weight: ~45 kg vs. ~29 kg • Height: 150 cm vs. 110 cm • Yet canines similar in size for both sexes
The Great Rift Valley
• Formed ~8 mya • Stretches ~3,500 miles • Over 2,000 feet deep
Distinguishing Cranial Traits H Erectus
• H. erectus has several unique features that distinguish it from early Homo and modern humans - Less facial prognathism and larger brain than H. habilis - Low forehead - Long and low braincase - Supraorbital torus - Occipital/nuchal torus • Pronounced ridge on rear-most occipital bone; neck muscles - Sagittal keel/ridge • Raised area where parietals meet on top of cranium - Thick cranial vault/bones - Cranium broadest at base - Dental reduction - Shovel-shaped incisors - No chin
Homo rudolfensis
• Questionable classification - Little postcranial material - Homo habilis, Paranthropus? • Age: ~2.4 - 1.6 mya • Location: East Africa • Encephalization: Brain size of ~700 cc • Body Size: Within range of modern humans (~5 feet tall) • Teeth: Smaller premolar and molars • Pelvic Girdle: Modifications similar to later Homo
